Multilayer LTCC Technology Research Articles

Effects of the Bi2O3-SiO2 addition on the sintering behavior and microwave dielectric properties of Zn1.8SiO3.8 ceramics

The effects of Bi2O3-SiO2 addition (denoted as BS) on the microstructure and microwave dielectric properties of Zn1.8SiO3.8 (denoted as ZS) ceramics have been investigated. It's proved that the addition of BS not only decreases the densification temperature effectively, but also contributes to the well microwave dielectric properties of ZS ceramics by the formation of Bi4(SiO4)3 phase at a low sintering temperature. In particular, when BS content was 20.0 wt%, the BS-added ceramics sintered at 875 °C for 2 h exhibited a low dielectric constant(Ɛr) of 6.78, a high quality factor(Q×f) of 28,742 GHz (at 15.7 GHz) and the temperature coefficient(τf) of the resonant frequency of −22.6 ppm/°C, which demonstrated a potential candidate for application of LTCC multilayer technology in millimeters and THz range.

LTCC微型巴伦设计

本文提出了一种基于LTCC (低温共烧陶瓷)技术的微型巴伦的设计与实现方法。此种巴伦采用Marchand型结构，运用LTCC多层三维立体集成技术，通过宽边耦合的螺旋型结构实现1/4波长耦合线，大大减小了巴伦的实际体积。随后通过带状线末端电容加载技术的改进型结构，近一步缩小了耦合线长，实现了结构的微型化。最终设计的巴伦工作频带1.5~3 GHz，具有插损小，幅度平坦性好，相位一致性高的优点，巴伦尺寸为2.5 mm × 3 mm × 1.2 mm。文章讨论了该巴伦工作原理、微型化的设计思路、三维结构，最后给出了设计的仿真和测试结果，两者一致性较好。 A method of designing and implementing a miniature LTCC balun is proposed in this paper. This kind of balun is based on the structure of Marchand microstrip balun in order to realize the mi-niaturization. LTCC multilayer 3D technology, broadband coupling spiral stripline and loading terminal capacitors structure have been used to achieve quarter-wave coupling line to reduce the size. The operation frequency ranges from 1 GHz to 3 GHz with the advantages of low insertion loss, well amplitude balance and strong phase consistency. The dimension was only 2.5 mm × 3 mm × 1.2 mm. The operation principle, design thoughts of miniaturization and the structure of balun were discussed in this paper. At last, the results from the simulation and those from the measurement are in good agreement.

A Compact Coupling Controllable Elliptical Filter Based on Multilayer LTCC

This paper presents a compact elliptical filter based on modified λ/4 resonators with separated electric and magnetic coupling paths. For the proposed second-order filters, transmission zero points are generated at either lower or upper stopband by controlling the relative coupling strength in the two paths of inter-stage resonators. Based on the topology and multilayer LTCC technology, a fourth-order bandpass filters operating at 5.2 GHz with a fractional bandwidth of 10% in 1.7 mm × 3 mm (0.0785λg × 0.1385λg) is designed and verified experimentally. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1789–1792, 2013

Design of Compact Stacked-Patch Antennas in LTCC Multilayer Packaging Modules for Wireless Applications

A simple procedure for the design of compact stacked-patch antennas is presented based on LTCC multilayer packaging technology. The advantage of this topology is that only one parameter, i.e., the substrate thickness (or equivalently the number of LTCC layers), needs to be adjusted in order to achieve an optimized bandwidth performance. The validity of the new design strategy is verified through applying it to practical compact antenna design for several wireless communication bands, including ISM 2.4-GHz band, IEEE 802.11a 5.8-GHz, and LMDS 28-GHz band. It is shown that a 10-dB return-loss bandwidth of 7% can be achieved for the LTCC (/spl epsiv//sub r/=5.6) multilayer structure with a thickness of less than 0.03 wavelengths, which can be realized using a different number of laminated layers for different frequencies (e.g., three layers for the 28-GHz band).